以下是我在Swift 4+中使用的音乐播放器。我将秒Int转换为可读的字符串格式

extension Int {
    var toAudioString: String {
        let h = self / 3600
        let m = (self % 3600) / 60
        let s = (self % 3600) % 60
        return h > 0 ? String(format: "%1d:%02d:%02d", h, m, s) : String(format: "%1d:%02d", m, s)
    }
}

像这样使用:

print(7903.toAudioString)

输出:2:11:43

以下是我在Swift 4+中使用的音乐播放器。我将秒Int转换为可读的字符串格式

extension Int {
    var toAudioString: String {
        let h = self / 3600
        let m = (self % 3600) / 60
        let s = (self % 3600) % 60
        return h > 0 ? String(format: "%1d:%02d:%02d", h, m, s) : String(format: "%1d:%02d", m, s)
    }
}

像这样使用:

print(7903.toAudioString)

输出:2:11:43

基于Vadian的回答，我写了一个扩展，它接受Double(其中TimeInterval是类型别名)，并输出一个格式化为时间的字符串。

extension Double {
  func asString(style: DateComponentsFormatter.UnitsStyle) -> String {
    let formatter = DateComponentsFormatter()
    formatter.allowedUnits = [.hour, .minute, .second, .nanosecond]
    formatter.unitsStyle = style
    return formatter.string(from: self) ?? ""
  }
}

这里是各种DateComponentsFormatter。UnitsStyle选项看起来像这样:

10000.asString(style: .positional)  // 2:46:40
10000.asString(style: .abbreviated) // 2h 46m 40s
10000.asString(style: .short)       // 2 hr, 46 min, 40 sec
10000.asString(style: .full)        // 2 hours, 46 minutes, 40 seconds
10000.asString(style: .spellOut)    // two hours, forty-six minutes, forty seconds
10000.asString(style: .brief)       // 2hr 46min 40sec

我正在使用这个扩展

 extension Double {

    func stringFromInterval() -> String {

        let timeInterval = Int(self)

        let millisecondsInt = Int((self.truncatingRemainder(dividingBy: 1)) * 1000)
        let secondsInt = timeInterval % 60
        let minutesInt = (timeInterval / 60) % 60
        let hoursInt = (timeInterval / 3600) % 24
        let daysInt = timeInterval / 86400

        let milliseconds = "\(millisecondsInt)ms"
        let seconds = "\(secondsInt)s" + " " + milliseconds
        let minutes = "\(minutesInt)m" + " " + seconds
        let hours = "\(hoursInt)h" + " " + minutes
        let days = "\(daysInt)d" + " " + hours

        if daysInt          > 0 { return days }
        if hoursInt         > 0 { return hours }
        if minutesInt       > 0 { return minutes }
        if secondsInt       > 0 { return seconds }
        if millisecondsInt  > 0 { return milliseconds }
        return ""
    }
}

用途不同

// assume myTimeInterval = 96460.397    
myTimeInteval.stringFromInterval() // 1d 2h 47m 40s 397ms

最新代码:XCode 10.4 Swift 5

extension Int {
    func timeDisplay() -> String {
        return "\(self / 3600):\((self % 3600) / 60):\((self % 3600) % 60)"
    }
}

根据GoZoner的答案，我写了一个扩展，以获得时间格式化根据小时，分钟和秒:

extension Double {

    func secondsToHoursMinutesSeconds () -> (Int?, Int?, Int?) {
        let hrs = self / 3600
        let mins = (self.truncatingRemainder(dividingBy: 3600)) / 60
        let seconds = (self.truncatingRemainder(dividingBy:3600)).truncatingRemainder(dividingBy:60)
        return (Int(hrs) > 0 ? Int(hrs) : nil , Int(mins) > 0 ? Int(mins) : nil, Int(seconds) > 0 ? Int(seconds) : nil)
    }

    func printSecondsToHoursMinutesSeconds () -> String {

        let time = self.secondsToHoursMinutesSeconds()

        switch time {
        case (nil, let x? , let y?):
            return "\(x) min \(y) sec"
        case (nil, let x?, nil):
            return "\(x) min"
        case (let x?, nil, nil):
            return "\(x) hr"
        case (nil, nil, let x?):
            return "\(x) sec"
        case (let x?, nil, let z?):
            return "\(x) hr \(z) sec"
        case (let x?, let y?, nil):
            return "\(x) hr \(y) min"
        case (let x?, let y?, let z?):
            return "\(x) hr \(y) min \(z) sec"
        default:
            return "n/a"
        }
    }
}

let tmp = 3213123.printSecondsToHoursMinutesSeconds() // "892 hr 32 min 3 sec"